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  • Mendelian人人类继承遗产 -- -- 高级

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    Why is understanding your family's genetic history important?
    ::为什么理解你家族的遗传史很重要?

    If a runs throughout your family, understanding this history can help evaluate your and other's genetic risks associated with that phenotype . This can be especially important as you decide to have your own children.
    ::如果在你的全家族中运行,理解这个历史可以帮助评估你和其他人的遗传风险,这些遗传风险都与这种苯并型有关。当你们决定生自己的孩子时,这可能特别重要。

    Mendelian Inheritance in Humans
    ::人类的门德利人继承遗产

    Inheritance in humans is not as straight-forward as that in the pea plant. Though some traits are inherited in simple Mendelian fashion, many are not. To analyze simple Mendelian inheritance a is often utilized. This is especially helpful in tracking the inheritance of a specific trait, characteristic or disorder (or allele) through a family.
    ::人类的继承没有豆厂那样直截了当。 虽然有些特征是以简单的门德利式方式继承的,但很多不是。 要分析简单的门德利继承,经常使用一个简单的门德利继承。 这特别有助于通过家庭跟踪特定特征、特征或障碍(或allele)的继承。

    Pedigrees
    ::集水地

    A pedigree is a chart which shows the inheritance of a trait over several generations. A pedigree is commonly created for families, as it can be used to outlines the inheritance patterns of familial traits or genetic disorders. It can be used to demonstrate autosomal dominant or recessive inheritance, or . Figure  shows a pedigree depicting recessive inheritance of a disorder through three generations. The trait is thought to be recessive as for the two individuals with the trait, neither has a parent who also has the trait. Geneticists may also be able to determine whether individuals with the trait in question are heterozygous or homozygous for the associated with the trait. When alleles are added to the pedigree shown ( A or a ), recessive inheritance in conformed.
    ::恋童癖是一种表明几代人遗传特征继承情况的图表。一种恋童癖通常为家庭创建,因为它可以用来概括家庭特征或遗传障碍的继承模式。它可以用来展示自主的支配性或休养性遗产,或.图示显示一种恋童癖,描述三代人间混乱的休养性遗产。该特征被认为与具有该特征的两个人一样是休养性的,也没有父母也具有该特征。遗传学家也可以确定具有该特征的个人是异体兹古斯人还是与该特征相关的同质古人。当阿列斯被添加到所显示的(A或a)中时,休养性遗产符合该特征。

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    In a pedigree, squares symbolize males, and circles represent females. A horizontal line joining a male and female indicates that the couple had offspring. Vertical lines indicate offspring which are listed left to right, in order of birth. Shading of the circle or square indicates an individual who has the trait being traced. The inheritance of the recessive trait is being traced. A is the dominant allele and a is recessive. An "affected" individual has the trait or characteristic (or disease) in question.

    Sex-linked or Autosomal?
    ::性关系还是Autosomal?

    A sex chromosome is a that determines the sex of an organism . Humans have two sex chromosomes, X and Y . Females have two X chromosomes ( XX ), and males have one X and one Y chromosome ( XY ). An autosome is any chromosome other than a sex chromosome. If a trait is autosomal it will affect males and females equally.
    ::性染色体是一种决定一个有机体性别的染色体,人类有两种性染色体,X和Y。 女性有两种X染色体(XX),男性有一种X和一种Y染色体(XY)。异体是任何一种染色体,但性染色体除外。如果特征是自动染色体,将对男性和女性产生同等影响。

    A sex-linked trait is a trait whose allele is found on a sex chromosome. The human X chromosome is significantly larger than the Y chromosome; there are many more genes located on the X chromosome than there are on the Y chromosome. As a result there are many more X-linked traits than there are Y-linked traits. Most sex-linked traits are recessive. Because males carry only one X chromosome, if they inherit a recessive sex-linked gene they will show a sex-linked condition; there is no dominant allele to offset the recessive allele .
    ::与性相关的特性是一种性染色体中发现异差的特征。人的X染色体比Y染色体大得多;X染色体中的基因比Y染色体中的基因多得多。因此,与性相关的特性比Y相联的特性多得多。与性相关的特性大多是休眠的。因为男性只携带一种X染色体,如果他们继承了一种与性相关的长期基因,他们就会显示一种与性相关的基因;没有占支配地位的异质来抵消与性相关的异差。

    Because of the recessive nature of most sex-linked traits, a female who shows a sex-linked condition would have to have two copies of the sex-linked allele, one on each of her X chromosomes. Figure shows how red-green colorblindness, a sex-linked disorder, is passed from parent to offspring.
    ::由于大多数与性别相关特征的暂时性性质,显示与性别相关状况的女性必须拥有两份与性别相关变异物的复制件,一份在她的X染色体上,图中显示了父母之间如何将红绿色的色盲(一种与性别相关的障碍)传给后代。

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    An X-linked disorder such as red-green colorblindness is normally passed onto the son of a carrier mother. Usually, females are unaffected as they have a second, normal copy of the allele on the second X chromosome. However, if a female inherits two defective copies of the allele, she will be colorblind. Therefore, every son of a colorblind woman will be colorblind.

    Dominant or Recessive?
    ::支配还是消沉?

    If the trait is autosomal dominant, every person with the trait will have a parent with the trait. If the trait is recessive, a person with the trait may have one, both or neither parent with the trait. An example of an autosomal dominant disorder in humans is Huntington’s disease (HD). Huntington’s disease is a degenerative disease of the . It has no obvious effect on phenotype until the person is aged 35 to 45 years old, so often these individuals have children. The disease is non-curable and, eventually, fatal. Every child born to a person who develops HD has a 50% chance of inheriting the defective allele from the parent.
    ::如果该特征具有自动细胞主导性,那么每个具有该特征的人都会有一个带有该特征的父母。如果该特征为休眠性,那么具有该特征的人可能有一个,无论是否双亲都有该特征。人体的自主细胞主导性障碍的一个例子就是亨廷顿的疾病(HD )。亨廷顿的疾病是该特征的退化性疾病。在35岁至45岁之前,该特征对苯型没有明显的影响,因此这些人往往有子女。该疾病不可治愈,最终是致命的。 发展HD的人所生的每个孩子都有50%的机会从父母那里继承有缺陷的灵长者。

    Heterozygous or Homozygous?
    ::异性人还是同性人?

    If a person is homozygous or heterozygous for the dominant allele of a trait, they will have that trait. If the person is heterozygous for a recessive allele of the trait, they will not show the trait. A person who is heterozygous for a recessive allele of a trait is called a carrier . Only people who are homozygous for a recessive allele of a trait will have the trait.
    ::如果一个人是同性古人或异性古人,作为某一特性的支配者,他们就会有这种特征;如果一个人是异性古人,作为该特性的休眠异性通灵,他们不会表现出这种特征;如果一个人是异性古人,则被称为异性异性异性通灵;只有同性古人,作为该特性的休眠异性通灵,才会有这种特征。

    Summary
    ::摘要

    • A pedigree can help geneticists discover if a trait, characteristic, or disease is inherited in a sex-linked, autosomal dominant, or autosomal recessive fashion.
      ::恋童癖者可以帮助遗传学家发现,一种特征、特征或疾病是否在与性别相关、具有自主性、具有自主性或自给性休眠状态中遗传。
    • The pedigree may also be able to demonstrate the genotype of the affected individuals.
      ::幼虫还可能能够证明受影响个人的基因型。

    Review
    ::回顾

    1. What is a pedigree?
      ::什么是恋童癖?
    2. Why, when males inherit a recessive sex-linked gene, will they show a sex-linked condition?
      ::为什么当男性继承了一种与性有关的后期基因时,他们会显示一种与性有关的条件?
    3. In a pedigree, squares are _______ and circles are ______. Fully shaded circles and squares represent ________. Half-shaded circle represents a _______.
      ::在小树枝中,方形为 ,圆圈为 。全阴暗的圆圈和方形代表 。半阴暗的圆圈代表 。
    4. Draw a pedigree that illustrates the following: a normal female with normal parents and two brothers with hemophilia A, a bleeding disorder that is inherited as an X‑linked recessive trait. What is the risk of hemophilia for her son or daughter?
      ::绘制一条血型图,说明如下:正常父母正常的普通女性和血友病A的两兄弟,血友病是一种遗传的出血紊乱症,作为与X有关的消亡特征。 儿子或女儿的血友病风险是什么?